Illegal labour immigration is increasingly a source of concern to politicians and the public in relatively rich countries within the Southern African Development Corporation (SADC). This paper examines the status of illegal immigration in Botswana and South Africa. The definition of illegal immigration is discussed. It draws extensively from similar experiences in the United States of America a...

Abstrac t . Stream landscapes are highly variable in space and time and, like terrestrial landscapes, the resources they contain are patchily distributed. Organisms may disperse among patches to fulfill life-history requirements, but biotic and abiotic factors may limit patch or locality occupancy. Thus, the dynamics of immigration and extinction determine, in part, the local structure of assem...

Does immigration generate jobs in an MSA, or do employment opportunities entice immigrant inflows to an MSA? Is immigration responsible for higher unemployment, or do foreign-born inflows cause increases in self-employment that lead to improvement in labor market conditions? The causal relationship between immigrants, job growth and unemployment is a politically and economically salient subject...

Objective. Survey research posits that Mexican Americans’ perceptions of the costs and benefits of immigration drive their opinions about immigration, but this research does not provide a clear picture of how Mexican Americans calculate these costs and benefits. This article aims to understand the processes that explain how Mexican Americans calculate the costs and benefits of Mexican immigrati...

BACKGROUND Many species are distributed as metapopulations in dynamic landscapes, where habitats change through space and time. Individuals locate habitat through dispersal, and the relationship between a species and landscape characteristics can have profound effects on population persistence. Despite the importance of connectivity in dynamic environments, few empirical studies have examined t...

OBJECTIVES To identify, explore and critique features of how practices associated with immigration medicine are socially organized. Specifically, how the work of designated medical practitioners (DMP) - physicians who conduct immigration medical examinations of prospective immigrants to Canada as contractors to the Canadian government department of Citizenship and Immigration Canada - is organi...

Researchers have suggested that perceptions of discrimination may vary depending on place of birth and the length of time spent living in the U.S., variables related to acculturation. However, the existing literature provides a mixed picture, with data suggesting that the effects of acculturation on perceptions of discrimination vary by race and other sociodemographic factors. This study evalua...

This study examined the relationships among cognitive variables, family immigration history, negative life events, and depressive symptoms in a sample of 306 low-income, urban fifth- and sixth-grade children. Explanatory style and negative automatic thoughts were the cognitive variables examined. There were three key findings. First, children who were immigrants reported significantly more depr...

Migratory birds often follow detours when confronted with ecological barriers, and understanding the extent and the underlying drivers of such detours can provide important insights into the associated cost to the annual energy budget and the migration strategies. The Qinghai-Tibetan Plateau is the most daunting geographical barrier for migratory birds because the partial pressure of oxygen is ...